This invention relates to a fuel injection system for an internal combustion engine and more particularly to an improved fuel injection system and control therefor that prevents the injection of fuel during starting at a time when combustion is not likely to occur.
As is well known, engine starting is a relatively difficult procedure. During starting the engine is cranked at a very low speed and fuel is supplied to the engine for starting purposes. However, there may be some instances when the fuel supply is premature and that the fuel introduced to the engine will not burn during the initial starting procedure. If this occurs, not only will fuel be wasted, but the spark plug of the engine can be wetted by the fuel and subsequent firing of the spark plug will not effect a spark and combustion.
For example, with supercharged engines, the supercharger may not deliver adequate air to the engine for combustion during initial cranking. If fuel is supplied during this time, the fuel can foul the spark plug and provide poor fuel economy and difficulties in starting.
It is, therefore, a principal object of this invention to provide an improved fuel supply system for an internal combustion engine wherein the fuel will not be supplied to the engine during starting until conditions exist where it will be ensured that the fuel will be burned when the spark plug is fired.
It is a further object of this invention to provide an improved method for starting an internal combustion engine.
It is a further object of this invention to provide a method of operating a fuel injected internal combustion engine and method of operating it wherein fuel will not be injected during starting until it will be ensured that combustion will occur.